type bi_op = And | Or
type q_type = Forall | Exists
type var = string
type equ_xor_op = Equ | Xor
module Env :
  sig
    type key = String.t
    type 'a t = 'a Map.Make(String).t
    val empty : 'a t
    val is_empty : 'a t -> bool
    val add : key -> 'a -> 'a t -> 'a t
    val find : key -> 'a t -> 'a
    val remove : key -> 'a t -> 'a t
    val mem : key -> 'a t -> bool
    val iter : (key -> 'a -> unit) -> 'a t -> unit
    val map : ('a -> 'b) -> 'a t -> 'b t
    val mapi : (key -> 'a -> 'b) -> 'a t -> 'b t
    val fold : (key -> 'a -> 'b -> 'b) -> 'a t -> 'b -> 'b
    val compare : ('a -> 'a -> int) -> 'a t -> 'a t -> int
    val equal : ('a -> 'a -> bool) -> 'a t -> 'a t -> bool
  end
val forall_string : string
val exists_string : string
val equ_string : string
val xor_string : string
val and_string : string
val or_string : string
val quantifier_open_string : string
val quantifier_close_string : string
val qpc_open_string : string
val qpc_close_string : string
